Fiber re-inforced plastic frame of self-opening umbrella

ABSTRACT

A frame of self-opening umbrella is provided wherein both ribs and spreaders are formed of lightweight fiber reinforced plastic (FRP) tube. Also there is no provision of pin and legs of second pivotal member between each link formed of stainless steel and each spreader. Each link has an upper hook end coupled to the pivotal hole in both the pivotal member and the spreader. Accordingly, the folded umbrella has a reduced space. The umbrella consists of simple constituent components and has an aesthetic appearance.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention generally relates to self-opening umbrellas and more particularly to such a lightweight umbrella frame formed of fiber reinforced plastic (FRP) tube having reduced space after closing and other advantageous features.

[0003] 2. Description of Related Art

[0004] It is common for people to carry an umbrella while going out. This is particularly true in countries having abundant rain year round. Thus, a lightweight while compact umbrella is desirable for many people. For obtaining the features of being compact and lightweight, a conventional stick umbrella comprises a plurality of ribs formed of metal, each having a first pivot joint, a ring slidable on center post having a plurality of second pivot joints, and a plurality of U-shaped spreaders (formed by punching thin metal material) each coupled between first and second pivot joints. However, for a self-opening umbrella having such configuration the strength thereof is not sufficient. In detail, the opening of self-opening umbrella is effected by suddenly expanding a spring secured onto ring. Also, such small pivot joints and spreaders are the main elements for buffering the elastic force of spring. However, pivot joints and spreaders tend to rust after long time of contacting rain. As a result, pivot joints and spreaders may detach from umbrella or deform, thereby shortening a useful life of the self-opening umbrella.

[0005] An improvement of above self-opening umbrella is effected by providing a frame of self-opening umbrella formed of fiber re-enforced plastic (FRP) due to its sufficient strength and lightweight features. As shown in FIG. 7, each of ribs R1 and spreaders R2 has a cross-section of circle. However, FRP based frame is disadvantageous for higher manufacturing cost and larger occupied space. As shown, second pivot joint P coupling spreader R2 and link B has two lugs P1 and a pin P3 pivotably coupled between lugs P1. Each of a plurality of links B is coupled between pin P3 and lower ring T1. With this configuration, the strong expanding force of spring S may be buffered in opening umbrella. In closing umbrella, lower ends of ribs R1, spreaders R2, second pivot joints P, and links B are folded toward one another in which links B are oblique and contact surface of upper ring T2. As a result, spreaders R2 slant outward and ribs Ri slant inward. This has the disadvantage of incapable of reducing space of umbrella to a minimum after closing. This in turn may cause inconvenience in storage and/or increase cost of transporting. While sizes of center post M and pivot joints P may be reduced in the FRP based umbrella the reduction effect is still limited. This is because the size of umbrella is predetermined. Also, the windproof factor of umbrella has to be considered. Thus, it is desirable to provide a lightweight frame formed of FRP having reduced space after closing and other advantageous benefits in order to overcome the above drawbacks of prior art.

SUMMARY OF THE INVENTION

[0006] It is an object of the present invention to provide a frame of self-opening umbrella wherein there is no provision of pivotal pin and legs for a pivotalmember between each of link formed of stainless steel and each spreader, and each link has an upper hook end coupled to the pivotal member of the spreader. Accordingly, the folded umbrella has a reduced space.

[0007] It is another object of the present invention to provide an FRP-based lightweight frame of self-opening umbrella wherein both ribs and spreader are hollow members formed of fiber reinforced plastic (FRP) tube for reducing weight.

[0008] It is still another object of the present invention to provide an FRP-based lightweight frame of self-opening umbrella having simple components and aesthetic appearance.

[0009] To accomplish the above objects, features and advantages, the present invention comprises:

[0010] a lower ring slidably mounted on a lower portion of the post;

[0011] an upper ring slidably mounted on an upper portion of the post;

[0012] a hub disposed on a top of the post;

[0013] a spring mounted on the post and biased between the lower ring and the upper ring;

[0014] a plurality of ribs, each being formed of fiber reinforced plastics (FRP) tube, and including an inner end thereof pivotally extended from the hub and a first pivotal member sleeved thereon;

[0015] a plurality of spreaders, each being formed of FRP tube and including an outer connecting element mounted at an outer end thereof pivotably coupled to the first connecting member of the rib and an inner connecting element mounted at an inner end thereof pivotably coupled to the upper ring;

[0016] a plurality of second pivotal member, each having a through bore therein and sleeved on the spreader; and

[0017] a plurality of links formed of stainless steel, each including a lower hook end coupled to the lower ring and an upper hook end coupled to the second pivotal member;

[0018] wherein a first pivotal hole is provided on each of the spreader and a second pivotal hole is provided on each of the second pivotal member, when each of the spreader is passed through the second pivotal member and inserted into the inner connecting element and assembled together, the first pivotal hole of spreader and the second pivotal hole of the second pivotal member are aligned together to thereby enable the upper hook end of each link to be pivotally coupled to the first and second pivotal holes.

[0019] The above and other objects, features and advantages of the present invention will become apparent from the following detailed description taken with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0020]FIG. 1 is an exploded perspective view of a first preferred embodiment of a portion of frame of self-opening umbrella according to the invention;

[0021]FIG. 2 is a side view of the assembled FIG. 1 umbrella, in an open condition;

[0022]FIG. 3 is an enlarged view of a portion of FIG. 2 umbrella in part section;

[0023]FIG. 4 is side view in part section showing a portion of frame of self-opening umbrella according to a second preferred embodiment of the invention;

[0024]FIG. 5 is side view showing a portion of frame of self-opening umbrella according to a third preferred embodiment of the invention;

[0025]FIG. 6 is a side view of frame of any of above embodiments in a closed condition; and

[0026]FIG. 7 is a side view of frame of a conventional self-opening umbrella in a closed condition.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] Referring to FIGS. 1 to 3, there is shown a frame of self-opening umbrella constructed in accordance with a first preferred embodiment of the invention. Frame of the umbrella is supported by a center post 10 comprising a lower ring 11 mounted on a lower portion of the post 10, an upper ring 13 mounted on an upper portion of the post 10, a hub 14 mounted on a top of the post 10, a spring 12 biased between the lower ring 11 and upper ring 13, a plurality of ribs 15, each having one end extended from the hub 14, a plurality of first pivotal members 16 sleeved on ribs 15, a plurality of spreaders 17 each having an inner connecting element 173 pivotally coupled to the upper ring 13 and an outer connecting element 172 pivotally coupled to the first pivotal members 16, a plurality of second pivotal members 18 sleeved on spreaders 17, and a plurality of links 19 formed of stainless steel, each having a lower hook end 191 pivotally coupled to the lower ring 11 and an upper hook end 192 pivotally coupled to the second pivotal member 18. The improvements of the invention are ribs 15, spreaders 17, inner and outer connecting elements 173 and 172 of spreaders 17, second pivotal members 18, and links 19. For obtaining the benefits of lightweight frame, simple components, and easy assembly, ribs 15 and spreaders 17 are elongate hollow bar formed of FRP tubes and a first pivotal hole 176 provided near the inner portion of each spreaders 17(see FIGS. 1 and 3). Also, first pivotal members 16, second pivotal members 18, inner connecting elements 173, and outer connecting elements 172 are formed of strong nylon by plastic injection molding.

[0028] In the embodiment, an inner end of inner connecting element 173 is pivotably coupled to upper ring 13. Spreader 17 comprises a first pivotal hole 176 on its surface. Correspondingly, second pivotal member 18 comprises a second pivotal hole 186 on its surface. Since the inner diameters of inner connecting element 173 and second pivotal member 18 are the same as outer diameter of spreader 17 so that spreader 17 may be passed through second pivotal member 18 and inserted into inner connecting element 173 for being. supported when holes 176 and 186 are aligned. Since the structure of second pivotal member 18 is simplified, the pin and lugs on the conventional joint of umbrella are eliminated in the invention. In detail, the sizes of holes 176 and 186 are the same and large enough to allow an upper hook end 192 of link 19 to smoothly insert through for being secured in the hollow FRP spreader 17. Also, as shown in FIG. 3, the loop portion 1920 of upper hook end 192 is permitted to smoothly move a distance defined by the bore of either hole 186 or 176. Moreover, hooked portion 1921 of upper hook 192 contacts inner wall of bore 170 of spreader 17. This invention further has the benefits of easy assembly and aesthetic appearance. Referring to FIG. 6, a closed condition of the invention is shown. Since there is no provision of pin and legs on the second pivotal member 18 between link 19 and spreader 17, also the arrangements of links 19, spreaders 17 and ribs 15 are substantially parallel to the center post 10 after folding the umbrella. Accordingly, the folded self-opening umbrella of the present invention has the advantages of reduced space, easy storage, and lower transporting cost.

[0029] Note that the coupling of inner connecting element 173 and second pivotal member 18 may be done by adhesive or ultrasonic welding. In the case of coupling by adhesive, adhesive is poured through aperture 174 on inner connecting element 173 and aperture 184 on second pivotal member 18 to secure second pivotal member 18 to spreader 17. In another consideration, since second pivotal member 18 is secured in spreader 17 by upper hook end 192 of link 19, such coupling by adhesive may be omitted. In other words, it is optional and totally decided by manufacture.

[0030] Referring to FIG. 4, there is shown a second embodiment of-the invention. The difference between first and second preferred embodiments is that the plastic second pivotal member 18 in the first embodiment is replaced by a metal tube second pivotal member 18′. The tube member 18′ also has a second pivotal hole 186′ on the surface aligned with the first pivotal hole 176.

[0031] Referring to FIG. 5, there is shown a third embodiment of the invention. The difference between first and third preferred embodiments is that inner connecting element 173 and second pivotal member 18 in the first embodiment are replaced by an integral second pivotal member 18A in which the inner connecting element 173 and the second pivotal member 18 are integrally formed as one unit. This can further simplify constituent components and assembly.

[0032] While the invention herein disclosed has been described by means of specific embodiments, numerous modifications and variations could be made thereto by those skilled in the art without departing from the scope and spirit of the invention set forth in the claims. 

What is claimed is:
 1. A self-opening umbrella having a frame supported by a center post, the frame comprising: a lower ring slidably mounted on a lower portion of the post; an upper ring slidably mounted on an upper portion of the post; a hub disposed on a top of the post; a spring mounted on the post and biased between the lower ring and the upper ring; a plurality of ribs, each being formed of fiber reinforced plastics (FRP) tube, and including an inner end thereof pivotally extended from the hub and a first pivotal member sleeved thereon; a plurality of spreaders, each being formed of FRP tube and including an outer connecting element mounted at an outer end thereof pivotably coupled to the first pivotal member of the rib and an inner connecting element mounted at an inner end thereof pivotably coupled to the upper ring; a plurality of second pivotal member, each having a through bore therein and sleeved on the spreader; and a plurality of links formed of stainless steel, each including a lower hook end coupled to the lower ring and an upper hook end coupled to the second pivotal member; wherein a first pivotal hole is provided on each of the spreader and a second pivotal hole is provided on each of the second pivotal member, when each of the spreader is passed through each of the second pivotal member and inserted into the inner connecting element and assembled together, the first pivotal hole of spreader and the second pivotal hole of the second pivotal member are aligned together to thereby enable the upper hook end of each link to be pivotally coupled to the first and second pivotal holes therein.
 2. The umbrella of claim 1, wherein each second pivotal member is formed of metal tube.
 3. The umbrella of claim 1, wherein the second pivotal member and the associated inner connecting element are integrally formed.
 4. The umbrella of claim 1, wherein an outer end of the inner connecting element contacts an inner end of the second pivotal member.
 5. The umbrella of claim 1, wherein each of the inner connecting element and the pivotal member are formed by plastic injection molding. 